<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style media="screen">
    body {
        font: 14px "Century Gothic", Futura, sans-serif;
        margin: 20px;
    }

    ol, ul {
        padding-left: 30px;
    }

    .board-row:after {
        clear: both;
        content: "";
        display: table;
    }

    .status {
        margin-bottom: 10px;
    }

    .square {
        background: #fff;
        border: 1px solid #999;
        float: left;
        font-size: 24px;
        font-weight: bold;
        line-height: 34px;
        height: 34px;
        margin-right: -1px;
        margin-top: -1px;
        padding: 0;
        text-align: center;
        width: 34px;
    }

    .square:focus {
        outline: none;
    }

    .kbd-navigation .square:focus {
        background: #ddd;
    }

    .game {
        display: flex;
        flex-direction: row;
    }

    .game-info {
        margin-left: 20px;
    }

    </style>
</head>
<body>
    <div id="errors" style="
    background: #c00;
    color: #fff;
    display: none;
    margin: -20px -20px 20px;
    padding: 20px;
    white-space: pre-wrap;
    "></div>
    <div id="container"></div>
    <script src="../js/react.js" charset="utf-8"></script>
    <script src="../js/react-dom.js" charset="utf-8"></script>
    <script src="../js/browser.min.js" charset="utf-8"></script>
    <script type="text/babel" charset="utf-8">
    window.addEventListener('mousedown', function(e) {
        document.body.classList.add('mouse-navigation');
        document.body.classList.remove('kbd-navigation');
    });
    window.addEventListener('keydown', function(e) {
        if (e.keyCode === 9) {
            document.body.classList.add('kbd-navigation');
            document.body.classList.remove('mouse-navigation');
        }
    });
    window.addEventListener('click', function(e) {
        if (e.target.tagName === 'A' && e.target.getAttribute('href') === '#') {
            e.preventDefault();
        }
    });
    window.onerror = function(message, source, line, col, error) {
        var text = error ? error.stack || error : message + ' (at ' + source + ':' + line + ':' + col + ')';
        errors.textContent += text + '\n';
        errors.style.display = '';
    };
    console.error = (function(old) {
        return function error() {
            errors.textContent += Array.prototype.slice.call(arguments).join(' ') + '\n';
            errors.style.display = '';
            old.apply(this, arguments);
        }
    })(console.error);

    /*----- react -----*/

    function Square(props) {
        return (
            <button className="square" onClick={() => props.onClick()}>
            {props.value}
            </button>
        );
    }

    class Board extends React.Component {

        renderSquare(i) {
            return <Square value={this.props.squares[i]} onClick={() => this.props.onClick(i)} />;
        }

        render() {

            return (
                <div>
                <div className="status">{status}</div>
                <div className="board-row">
                {this.renderSquare(0)}
                {this.renderSquare(1)}
                {this.renderSquare(2)}
                </div>
                <div className="board-row">
                {this.renderSquare(3)}
                {this.renderSquare(4)}
                {this.renderSquare(5)}
                </div>
                <div className="board-row">
                {this.renderSquare(6)}
                {this.renderSquare(7)}
                {this.renderSquare(8)}
                </div>
                </div>
            );
        }
    }

    class Game extends React.Component {

        constructor() {
            super()
            this.state = {
                history: [
                    {
                        squares: Array(9).fill(null)
                    }
                ],
                xIsNext: true,
                stepNumber: 0,
            }
        }

        handleClick(i) {
            const history = this.state.history.slice(0, this.state.stepNumber+1)
            const current = history[history.length-1]
            const squares = current.squares.slice()

            if(calculateWinner(squares) || squares[i]) {
                return
            }
            squares[i] = this.state.xIsNext ? 'X' : 'O'
            this.setState({
                history: history.concat([{
                    squares: squares
                }]),
                xIsNext: !this.state.xIsNext,
                stepNumber: history.length,
            })
        }

        jumpTo(step) {
            this.setState({
                stepNumber: step,
                xIsNext: (step % 2) ? false: true
            })
        }

        render() {

            const history = this.state.history
            const current = history[this.state.stepNumber]
            const winner = calculateWinner(current.squares)

            let status
            if(winner) {
                status = 'Winner: ' + winner
            } else {
                status = 'Next player: ' + (this.state.xIsNext ? 'X': '0')
            }

            const moves = history.map((step, move) => {
                const desc = move ? 'Move #' + move : 'Game start'
                return (
                    <li key={move}>
                        <a href="#" onClick={() => this.jumpTo(move)}>{desc}</a>
                    </li>
                )
            })

            return (
                <div className="game">
                <div className="game-board">
                <Board
                    squares={current.squares}
                    onClick={(i) => this.handleClick(i)}
                />
                </div>
                <div className="game-info">
                <div>{status}</div>
                <ol>{moves}</ol>
                </div>
                </div>
            );
        }
    }

    // ========================================

    ReactDOM.render(
        <Game />,
        document.getElementById('container')
    );

    function calculateWinner(squares) {
        const lines = [
            [0, 1, 2],
            [3, 4, 5],
            [6, 7, 8],
            [0, 3, 6],
            [1, 4, 7],
            [2, 5, 8],
            [0, 4, 8],
            [2, 4, 6],
        ];
        for (let i = 0; i < lines.length; i++) {
            const [a, b, c] = lines[i];
            if (squares[a] && squares[a] === squares[b] && squares[a] === squares[c]) {
                return squares[a];
            }
        }
        return null;
    }


    </script>
</body>
</html>
